CN106335889B - The method for producing sodium tripolyphosphate using thick sodium pyrophosphate - Google Patents
The method for producing sodium tripolyphosphate using thick sodium pyrophosphate Download PDFInfo
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- CN106335889B CN106335889B CN201610688474.9A CN201610688474A CN106335889B CN 106335889 B CN106335889 B CN 106335889B CN 201610688474 A CN201610688474 A CN 201610688474A CN 106335889 B CN106335889 B CN 106335889B
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- sodium
- sodium pyrophosphate
- thick
- tripolyphosphate
- sodium tripolyphosphate
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/26—Phosphates
- C01B25/38—Condensed phosphates
- C01B25/40—Polyphosphates
- C01B25/41—Polyphosphates of alkali metals
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Abstract
The present invention relates to a kind of utilization methods of thick sodium pyrophosphate, specifically disclose a kind of method producing sodium tripolyphosphate using thick sodium pyrophosphate.Include the following steps：(1) thick sodium pyrophosphate is washed；(2) press filtration is carried out to washed-residue；(3) removing impurities agent is added into solution except metal ion for dissolving filter cake；(4) press filtration is carried out to removing impurities solution；(5) decolorising agent depigmentation is added, adds phosphoric acid, accelerates dissolving, finally plus lye adjusts pH value；(6) it after crystallisation by cooling, then carries out being separated by solid-liquid separation to obtain sodium pyrophosphate crystal；(7) using gained sodium pyrophosphate crystal as the raw materials for production of production sodium tripolyphosphate.The advantage of the invention is that：1) resource reclaim that gives up is realized；2) implement simple, production efficiency height；3) gained sodium pyrophosphate crystal purity is high；4) production cost of sodium tripolyphosphate is reduced.
Description
Technical field
The present invention relates to a kind of process for refining of thick sodium pyrophosphate, especially a kind of utilization method of thick sodium pyrophosphate.
Background technology
The preparation method of sodium tripolyphosphate is mostly by the way that sodium tripolyphosphate, wherein neutralizer directly is made with neutralizer at present
It is formulated using phosphoric acid and liquid caustic soda, phosphoric acid and burning is added in proportion or by metering to neutralizer make-up tank when production
Then alkali carries out subsequent technique and sodium tripolyphosphate is made.The technique belongs to the ripe traditional handicraft continued to use for many years, but with city
Variation, in recent years the price of caustic soda and phosphoric acid rise steadily, cause the cost of sodium tripolyphosphate constantly to rise, profit margin
It is smaller and smaller, in the edge of loss.
Thick sodium pyrophosphate is a kind of waste of pesticide industry, its inside is production trimerization containing a large amount of sodium, phosphorus composition
The essential component of sodium phosphate.
Also considerably less, the Publication No. CN about reporting for work for the method for preparing sodium tripolyphosphate using thick sodium pyrophosphate
The method that the patent document of 104003366A discloses a kind of utilization 12 water sodium pyrophosphates production sodium tripolyphosphate, but its institute
The not thick sodium pyrophosphate used, therefore production cost is higher, and it is not related to the utilization method about thick sodium pyrophosphate.Publication number
A kind of method producing sodium tripolyphosphate using thick sodium pyrophosphate is disclosed for the patent document of CN104843662A, is first to use
Orthophosphoric acid sodium salt is made in thick sodium pyrophosphate, recycles sodium orthophosphate that disodium hydrogen phosphate and tertiary sodium phosphate is made, and trimerization phosphorus is finally made
Sour sodium.This process employs thick sodium pyrophosphate, production cost is reduced from the angle of raw material, but this method to temperature, pressure all
There are very high requirement, and the step of must being hydrolyzed by natural cooling and multistep, needs a set of special equipment that could implement, it is difficult to implement
Spend larger, technique is cumbersome, and the production cycle is long, and it is difficult to have that it, which is directly added into the method that reaction is hydrolyzed in cleaner and decolorising agent,
Effect removes the impurity and pigment in thick sodium pyrophosphate, is finally difficult to obtain qualified sodium tripolyphosphate product.
Invention content
To solve existing produced using thick sodium pyrophosphate asking for special equipment is needed present in the method for sodium tripolyphosphate
Topic, the present invention provides a kind of methods producing sodium tripolyphosphate using thick sodium pyrophosphate.Inventor is successfully opened by experiment
It sends out thick sodium pyrophosphate and is added in the neutralizer of traditional handicraft in the form of liquid and crystal after process for refining and produce three
The method of polyphosphate sodium, this method can be realized using common apparatus, not only ensure that every quality index of sodium tripolyphosphate,
And reduce the cost of material of production sodium tripolyphosphate.
The technical solution adopted in the present invention is：The method for producing sodium tripolyphosphate using thick sodium pyrophosphate, including it is following
Step：
(1) thick sodium pyrophosphate is washed, so that wherein sodium chloride is dissolved in water, filters to obtain washed-residue；
(2) press filtration is carried out to washed-residue, obtains filter cake and first-time filtrate；
(3) dissolving filter cake, and removing impurities agent is added into solution and removes metal ion, obtain removing impurities solution；
(4) secondary press filtration is carried out to removing impurities solution, obtains secondary filtrate；
(5) decolorising agent depigmentation is added into secondary filtrate, adds phosphoric acid, accelerates dissolving, finally adds lye tune
PH value is saved to 7.5~8.5, is made into refined liquid, a portion refined liquid is sent into the neutralization in tripolyphosphate process for producing sodium
Liquid prepares raw materials for production of the workshop section with phosphoric acid and liquid caustic soda mixed preparing neutralizer as production sodium tripolyphosphate；
(6) it after carrying out crystallisation by cooling to another part refined liquid, then carries out being separated by solid-liquid separation to obtain sodium pyrophosphate crystal and mother liquor；
(7) by the neutralizer that gained sodium pyrophosphate crystal is sent into tripolyphosphate process for producing sodium prepare workshop section and phosphoric acid and
Raw materials for production of the liquid caustic soda mixed preparing neutralizer as production sodium tripolyphosphate.
The present invention uses first is refined into sodium pyrophosphate crystal by thick sodium pyrophosphate, then using sodium pyrophosphate crystal as in tradition
The raw material that sodium tripolyphosphate is prepared with method uses, and avoids directly preparing present in sodium tripolyphosphate technique using thick sodium pyrophosphate
Technical problem.And it is added what removing impurities agent and decolorising agent were hydrolyzed directly in thick sodium pyrophosphate cleaning solution compared with the existing technology
Method, process for purification of the invention can preferably remove the impurity in thick sodium pyrophosphate.Since what is finally obtained is sodium pyrophosphate
Crystal, almost without sodium chloride, sulfide and other impurities, so to the Influence of production very little of sodium tripolyphosphate.
As a further improvement on the present invention, it will be recycled in the desalinization of soil by flooding or leaching water return to step (1) of gained in step (1),
For washing thick sodium pyrophosphate；Desalinization of soil by flooding or leaching water is pumped into buffer pool after the sodium chloride content in desalinization of soil by flooding or leaching water reaches saturation, is buffered
The desalinization of soil by flooding or leaching water in pond is exchanged heat by pumping into sodium tripolyphosphate tail gas air hose chuck with high-temperature tail gas, and the desalinization of soil by flooding or leaching water after heat exchange returns
Spraying and sprinkling evaporation is carried out to buffer pool.Brine after the desalinization of soil by flooding or leaching is to return to desalinization of soil by flooding or leaching slot to reuse, but work as salt content accumulation to saturation
When cannot reuse again, the average saturation desalinization of soil by flooding or leaching water that generate 1.5 cubic metres per hour cannot since its COD contents are exceeded
Desalinization of soil by flooding or leaching water is squeezed into sodium tripolyphosphate tail gas air hose by arbitrarily discharge so desalinization of soil by flooding or leaching water treatment technology has also been devised in the present invention with pump
Chuck, since air hose temperature is up to 200 DEG C, desalinization of soil by flooding or leaching water is heated to 80~90 DEG C after entering chuck, is then return to buffer pool, lead to
It crosses 84 spraying nozzles and completes misty evaporation in air by moisture, thus generated almost without any waste water, reach horizontal
Weighing apparatus.
As a further improvement on the present invention, the dissolving method of filter cake is in step (3)：In dissolving tank steam by solution
It is heated to 85 DEG C and is stirred dissolving.It since filter cake cannot dissolve at normal temperatures, needs to dissolve by heating it, this method is
Easier and effect preferably dissolves by heating method.
As a further improvement on the present invention, the crystallisation by cooling described in step (6) and solid-liquid separating method are：It will refine
Liquid pump is sent into DTB crystallizers, 5 DEG C of water that the refined liquid inside DTB crystallizers is sent by forced circulation pump and refrigerating water sets
Exchange heat cooling inside heat exchanger；When solution temperature is down to 15 DEG C, it is delivered to head tank and enters centrifuge and be centrifuged
Obtain sodium pyrophosphate crystal.DTB types crystallizer (guide shell crystallizer) belongs to typical internal circulation crystallizer for crystal slurry.Due to tying
Inner draft tube is arranged in brilliant device, forms circulation canal, and magma is made to have good mixing condition, it is only necessary to very low pressure head, just
It can make to realize good interior cycle in device.
As a further improvement on the present invention, the removing impurities agent described in step (3) is vulcanized sodium.
As a further improvement on the present invention, the decolorising agent described in step (5) is activated carbon.
As a further improvement on the present invention, mother liquid obtained feeding mother liquor tank in step (6) is stored, as step (3)
The solvent of middle dissolving filter cake is recycled.To make full use of remaining sodium pyrophosphate resource in mother liquor.
As a further improvement on the present invention, in step (2) in gained filter cake, sodium chloride mass concentration is less than 2.5%.
As a further improvement on the present invention, refined liquid and step that neutralizer prepares workshop section are routed directly in step (5)
(6) mass ratio that the refined liquid of crystallisation by cooling is used in is 1:1.5.Inventor is found through experiments that, when neutralizer prepares workshop section
When excessive purification is added, the impurity index that may result in the sodium tripolyphosphate of generation is above standard, and generation does not conform to
Lattice product, and partially liq and partial crystals are added and do not influence every quality of sodium tripolyphosphate completely under suitable ratio
Index
As a further improvement on the present invention, the press filtration mode in the step (2) and step (4) is to pass through plate compression
Machine carries out press filtration, to improve filter cake solid content.
The beneficial effects of the invention are as follows：1) it is effectively utilized the thick sodium pyrophosphate of pesticide industry by-product, realizes that secondary useless resource is returned
It receives；2) special equipment input is not needed, simple, production efficiency height is implemented；3) improve the process for refining of thick sodium pyrophosphate, gained is burnt
Sodium phosphate crystal purity is high；4) production cost of sodium tripolyphosphate is reduced.
Description of the drawings
Fig. 1 is the process flow chart of the present invention.
Specific implementation mode
The following further describes the present invention with reference to the drawings.
As shown in Figure 1, thick sodium pyrophosphate initially enters desalinization of soil by flooding or leaching slot removes most of sodium chloride by the desalinization of soil by flooding or leaching, then into sheet frame
Filter press press filtration carries out a press filtration, and filter cake contains a large amount of sodium pyrophosphates, and sodium chloride mass concentration is less than 2.5%, then is dissolving
Solution is heated to 85 DEG C with steam and is stirred dissolving by slot, and when dissolving is added vulcanized sodium and removes metal ion, and insoluble matter is hydrogen-oxygen
Change the impurity such as copper, and go to carry out secondary press filtration, filtrate is sodium pyrophosphate solution, and activated carbon depigmentation is added in filtrate, is added
Phosphoric acid accelerates dissolving, last liquid feeding alkali adjusting pH value to 7.5~8.5 to be configured to refined liquid.A part of refined liquid is directly gone
Sodium tripolyphosphate neutralizer is prepared workshop section and is used, and another part refined liquid is pumped into DTB crystallizers, the essence inside DTB crystallizers
Liquid processed is exchanged heat cooling by 5 DEG C of water that forced circulation pump and refrigerating water sets are sent inside heat exchanger；Wait for that solution temperature is down to
At 15 DEG C, after crystallization becomes floccule, it is delivered to head tank and enters centrifuge and be centrifuged to obtain sodium pyrophosphate crystal, it is burnt
Phosphoric acid sodium crystal is added the neutralizer in tripolyphosphate process for producing sodium and prepares in workshop section and phosphoric acid and liquid caustic soda mixed preparing
Raw materials for production with liquid as production sodium tripolyphosphate.Above-mentioned desalinization of soil by flooding or leaching water is returned for washing thick sodium pyrophosphate；When desalinization of soil by flooding or leaching water
In sodium chloride content reach saturation after desalinization of soil by flooding or leaching water is pumped into buffer pool, the desalinization of soil by flooding or leaching water of buffer pool is by pump into tripolyphosphate
Sodium tail gas air hose chuck exchanges heat with high-temperature tail gas, and the desalinization of soil by flooding or leaching water after heat exchange returns to buffer pool and carries out spraying and sprinkling evaporation.
Analysis of Economic Value after the present invention is implemented sees below Tables 1 and 2：
Table 1：Use the cost analysis of 1 ton of thick sodium pyrophosphate
Table 2：Thick sodium pyrophosphate per ton is used to produce the value of sodium tripolyphosphate generation
Year economic benefit (monthly adding 3000 tons of thick sodium pyrophosphate) after present invention implementation：
(2240.01-1754.108) × 3000 × 12=17492472 members/year.
Claims (9)
1. using the method for thick sodium pyrophosphate production sodium tripolyphosphate, include the following steps：
（1）Thick sodium pyrophosphate is washed, wherein sodium chloride is made to be dissolved in water, filters to obtain washed-residue and desalinization of soil by flooding or leaching water；
It is characterized in that：It further include step（2）~（7）, specially：
（2）Press filtration is carried out to washed-residue, obtains filter cake and first-time filtrate；
（3）Dissolving filter cake, and removing impurities agent is added into solution and removes metal ion, obtain removing impurities solution；
（4）Secondary press filtration is carried out to removing impurities solution, obtains secondary filtrate；
（5）Decolorising agent depigmentation is added into secondary filtrate, adds phosphoric acid, accelerates dissolving, finally plus lye adjusts pH
Value is made into refined liquid to 7.5~8.5, and the neutralizer that a portion refined liquid is sent into tripolyphosphate process for producing sodium is matched
Raw materials for production of the workshop section processed with phosphoric acid and liquid caustic soda mixed preparing neutralizer as production sodium tripolyphosphate；
（6）After carrying out crystallisation by cooling to another part refined liquid, then carry out being separated by solid-liquid separation to obtain sodium pyrophosphate crystal and mother liquor；Step
（5）In be routed directly to neutralizer prepare workshop section refined liquid and step（6）In for the mass ratio of refined liquid of crystallisation by cooling be
1:1.5；
（7）The neutralizer that gained sodium pyrophosphate crystal is sent into tripolyphosphate process for producing sodium is prepared into workshop section and phosphoric acid and liquid
Raw materials for production of the caustic soda mixed preparing neutralizer as production sodium tripolyphosphate.
2. the method according to claim 1 for producing sodium tripolyphosphate using thick sodium pyrophosphate, it is characterised in that：By step
（1）The desalinization of soil by flooding or leaching water return to step of middle gained（1）Middle recycling, for washing thick sodium pyrophosphate；Sodium chloride in desalinization of soil by flooding or leaching water
Desalinization of soil by flooding or leaching water is pumped into buffer pool by content after reaching saturation, and the desalinization of soil by flooding or leaching water of buffer pool enters sodium tripolyphosphate tail gas air hose by pump
Chuck exchanges heat with high-temperature tail gas, and the desalinization of soil by flooding or leaching water after heat exchange returns to buffer pool and carries out spraying and sprinkling evaporation.
3. the method according to claim 1 or 2 for producing sodium tripolyphosphate using thick sodium pyrophosphate, it is characterised in that：Step
Suddenly（3）The dissolving method of middle filter cake is：Solution is heated to 85 DEG C with steam in dissolving tank and is stirred dissolving.
4. the method according to claim 1 or 2 for producing sodium tripolyphosphate using thick sodium pyrophosphate, it is characterised in that：Step
Suddenly（6）Described in crystallisation by cooling and solid-liquid separating method be：Refined liquid is pumped into DTB crystallizers, inside DTB crystallizers
Refined liquid is exchanged heat cooling by 5 DEG C of water that forced circulation pump and refrigerating water sets are sent inside heat exchanger；Wait for that solution temperature drops
When to 15 DEG C, it is delivered to head tank and enters centrifuge and be centrifuged to obtain sodium pyrophosphate crystal.
5. the method according to claim 1 or 2 for producing sodium tripolyphosphate using thick sodium pyrophosphate, it is characterised in that：Step
Suddenly（3）Described in removing impurities agent be vulcanized sodium.
6. the method according to claim 1 or 2 for producing sodium tripolyphosphate using thick sodium pyrophosphate, it is characterised in that：Step
Suddenly（5）Described in decolorising agent be activated carbon.
7. the method according to claim 1 or 2 for producing sodium tripolyphosphate using thick sodium pyrophosphate, it is characterised in that：It will
Step（6）In the storage of mother liquid obtained feeding mother liquor tank, as step（3）The solvent of middle dissolving filter cake is recycled.
8. the method according to claim 1 or 2 for producing sodium tripolyphosphate using thick sodium pyrophosphate, it is characterised in that：Step
Suddenly（2）In middle gained filter cake, sodium chloride mass concentration is less than 2.5%.
9. the method according to claim 1 or 2 for producing sodium tripolyphosphate using thick sodium pyrophosphate, it is characterised in that：Institute
State step（2）And step（4）In press filtration mode be that press filtration carried out by plate and frame filter press.
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Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106946237B (en) * | 2017-03-14 | 2019-09-17 | 镇江江南化工有限公司 | A method of reducing generated solid waste when crude product sodium pyrophosphate production sodium pyrophosphate product |
| CN106882781B (en) * | 2017-03-14 | 2019-03-15 | 镇江江南化工有限公司 | A kind of method decolourized when crude product sodium pyrophosphate purification production sodium pyrophosphate product |
| CN106809811B (en) * | 2017-03-14 | 2019-06-14 | 镇江江南化工有限公司 | A method of sodium pyrophosphate is prepared using crude product sodium pyrophosphate |
| CN109399598B (en) * | 2018-12-28 | 2021-08-10 | 湖北泰盛化工有限公司 | Method for producing sodium pyrophosphate and sodium chloride by purifying crude sodium pyrophosphate |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104003366A (en) * | 2014-04-24 | 2014-08-27 | 四川蓝海化工（集团）有限公司 | Novel sodium tripolyphosphate production technology |
| CN104477864A (en) * | 2014-12-22 | 2015-04-01 | 什邡圣地亚化工有限公司 | Technology for producing phosphate from pyrophosphate |
| CN104843662A (en) * | 2015-04-15 | 2015-08-19 | 绵阳市神龙饲料有限公司 | Preparation method for phosphoric acid sodium salts |
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2016
- 2016-08-18 CN CN201610688474.9A patent/CN106335889B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104003366A (en) * | 2014-04-24 | 2014-08-27 | 四川蓝海化工（集团）有限公司 | Novel sodium tripolyphosphate production technology |
| CN104477864A (en) * | 2014-12-22 | 2015-04-01 | 什邡圣地亚化工有限公司 | Technology for producing phosphate from pyrophosphate |
| CN104843662A (en) * | 2015-04-15 | 2015-08-19 | 绵阳市神龙饲料有限公司 | Preparation method for phosphoric acid sodium salts |
Non-Patent Citations (1)
| Title |
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| 《利用粗品焦磷酸钠提纯生产磷酸钠盐产品技改项目》;豆丁网;《豆丁网》;20140307;第1-25页 * |
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